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A rocket has no bullet to push off of. Rockets do not expel solid chunks. Solids do not move like fluids. Pressure gradient force moves the gas and the gas pushes the bullet. The gas is bounces off the bullet and pushes the gun.

False. And very silly: How can the gas suddenly push the gun after having bounced off a bullet, if you claim that it can't push if from "bouncing out" from the gun in the first place?

The gas pressure in the barrel pushes both ways; against the gun and against the bullet. However, the bullet is not important for the rocket effect. The gas itself is accelerated, instead.

Hans

__________________Experience is an excellent teacher, but she sends large bills.

Gingervytes, when you can take a break from pretending that Newtonís Third Law only applies when you find it convenient, would you be so kind as to answer the questions and refutations Iíve already put to you, but you have ignored so far? Here, Iíll repeat them for you:

Originally Posted by sts60

Well, the SpaceX launch I watched last week from just outside the Vehicle Assembly Building was a commercial endeavor - they had a customer who paid them to put their vehicle into orbit. So NASA provided launch infrastructure, but had nothing to do with the rocketry in space. Thatís just the latest example of decades of commercial space flight. Not to mention Soviet/Russian, European, Chinese, Indian, Japanese, and other countriesí national and commercial space programs. The idea that the theory, let alone the practice, of rocketry somehow belongs to NASA is manifestly false.

On a more specific note, Iíve personally commanded a spacecraft to ďfireĒ its thruster to move away from the Shuttle - a cold gas N2 rocket with a whopping few ounces of thrust. It worked just fine, as we observed the results directly - including tracking the vehicle with our own (not just NASAís) S-band antenna. So, yes, I have direct personal experience that rockets work in a vacuum.

Originally Posted by sts60

Your garbled interpretation of Newtonian mechanics aside, why would video be better than tracking data, or radar, or onboard inertial telemetry, the primary ways we (people who launch and operate spacecraft for a living) actually measure the response of spacecraft to rocket operation in space?

Bonus question: you do understand that NASA did not invent the equations of motion, nor the equations of rocketry, and that spacecraft are routinely operated by civil, military, and commercial organizations from many nations? Right?

No you haven't, as evidenced by your continuing to make the same mistakes the video does. You don't understand what momentum is, where it comes from, and what its effects are. This is why you keep posing what you wrongly think are analogies to rockets, but conflate elementary concepts like gravity.

You were shown how the video conflates other physical effects such as gravity and buoyancy. You have not rehabilitated your argument in the face of that demonstration. Simply repeating a debunked claim does not overcome its refutation.

Remember when self-styled super-engineer Anders was over on apollohoax, blithely not understanding conservation of energy? This reminds me of that, in particular the counterexample I gave him of a non-propulsive mass jettison. Dunning-Krueger in action.

No you haven't, as evidenced by your continuing to make the same mistakes the video does. You don't understand what momentum is, where it comes from, and what its effects are. This is why you keep posing what you wrongly think are analogies to rockets, but conflate elementary concepts like gravity.

You were shown how the video conflates other physical effects such as gravity and buoyancy. You have not rehabilitated your argument in the face of that demonstration. Simply repeating a debunked claim does not overcome its refutation.

ďConservation of momentum is a fundamental law of physics which states that the momentum of a system is constant if there are no external forces acting on the system. It is embodied in Newton's first law (the law of inertia).Ē the external force is pressure gradient force, not from the rocket

“Conservation of momentum is a fundamental law of physics which states that the momentum of a system is constant if there are no external forces acting on the system. It is embodied in Newton's first law (the law of inertia).” the external force is pressure gradient force, not from the rocket

No, that's not an external force. Gravity, for example, would be an external force for a rocket. The propellant contained in the rocket, and sharing its velocity state and mechanically coupled to it, is part of the rocket system. Since you were asked twice to address the refutation of your video, and you have declined both times to do so, can we agree that you have no rejoinder for the refutation and cannot rehabilitate the claims your video makes?

ďConservation of momentum is a fundamental law of physics which states that the momentum of a system is constant if there are no external forces acting on the system. It is embodied in Newton's first law (the law of inertia).Ē the external force is pressure gradient force, not from the rocket

I can barely believe that a person can so willfully ignorant about basic concepts and the results of well established facts.

After all, rockets have been successfully operating in the vacuum of space for well over 60 years now.

In fact, if rockets could not operate in the vacuum of space, then it would not have been possible for the Apollo astronauts to go to the Moon and back in 1969 (plus a few more times after that).

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Remember when self-styled super-engineer Anders was over on apollohoax, blithely not understanding conservation of energy? This reminds me of that, in particular the counterexample I gave him of a non-propulsive mass jettison. Dunning-Krueger in action.

There's a two-player Cheese Shop game in The Brand New Monty Python Bok, in which one player - the customer - asks for various different types of cheese, and the other - the shopkeeper - has to think up a new excuse as to why he hasn't got it. I think it's important, for those who are trying to persuade Gingervytes of his/her error, to realise that he/she is not seeking information or correction here, but playing a variant of the Cheese Shop game, in the role of shopkeeper.

Dave

__________________Me: So what you're saying is that, if the load carrying ability of the lower structure is reduced to the point where it can no longer support the load above it, it will collapse without a jolt, right?

There's a two-player Cheese Shop game in The Brand New Monty Python Bok, in which one player - the customer - asks for various different types of cheese, and the other - the shopkeeper - has to think up a new excuse as to why he hasn't got it. I think it's important, for those who are trying to persuade Gingervytes of his/her error, to realise that he/she is not seeking information or correction here, but playing a variant of the Cheese Shop game, in the role of shopkeeper.

Solid chunk is one word. Important part is solid becuase it doesn’t follow fluid dynamics

Wrong is also one word, that that you are

Who many words is solid chunk?

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You know what I meant. Solid chunk is one piece. You could just say a piece of solid. Iím sorry that your English is weak

Because when you realise you've said something truly stupid, it's always best to double down, right?

Dave

__________________Me: So what you're saying is that, if the load carrying ability of the lower structure is reduced to the point where it can no longer support the load above it, it will collapse without a jolt, right?

I can barely believe that a person can so willfully ignorant about basic concepts and the results of well established facts.

After all, rockets have been successfully operating in the vacuum of space for well over 60 years now.

In fact, if rockets could not operate in the vacuum of space, then it would not have been possible for the Apollo astronauts to go to the Moon and back in 1969 (plus a few more times after that).

To posters familiar with this kind of argument: I run on the assumption that woo believers were never properly educated on the fundemental physics, then they run across a woo peddler who slides in absurdities under the guise of critical analysis. It would by necessity have to be dumbed down and missing critical components to be plausible, but seem to the new woo recipient to be scientifically sound, hence the resistance to correction. Is this the typical M.O.? I confess the psychology is a little fascinating

__________________"Half of what he said meant something else, and the other half didn't mean anything at all" -Rosencrantz, on Hamlet

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